Hexasodium 4,4'-[vinylenebis[(3-sulphonato-4,1-phenylene)imino[6-morpholino-1,3,5-triazine-4,2-diyl]imino]]bis[5-hydroxy-6-(phenylazo)naphthalene-2,7-disulphonate]

Endpoint summary

Additional information

Short-term toxicity to fish

Key study

The acute toxicity of the test item (88% purity) to fish (zebrafish) was determined according to the OECD TG 203 (1992) and EU Method C.1 (2008). A static limit test with one application at the test start was conducted with a test item concentration of 114 mg/L, corresponding to 100 mg/L, corrected for purity. The test item amount was weighed and added directly to the water in the test vessel. The solution was mixed with an ultraturrax (1 min, 17000 rpm). The test duration was 96 hours. 7 test organisms each were exposed to the test item solution and the control. The water quality parameters temperature, pH-value and oxygen saturation measured at 0, 24, 48, 72 and 96 hours were within the acceptable limits. The concentrations of the test item in the limit test concentration and in the control were analytically verified via spectrophotometric analysis at the start and end of the exposure (0 and 96 hours). At the start of the exposure (0 hours), the measured concentration of the test item, corrected for purity, was 96 mg/L for the test item solution. At the end of exposure (96 hours), the value was 97 mg/L. There was no test item found in the control samples either at the start or the end of the exposure period. Therefore, all effect values were based on the nominal concentration of the test item, corrected for purity. The LC50 after 2, 24, 48, 72 and 96 -h was > 100 mg/L, corrected for purity. The 96 -h LC100 value was > 100 mg/L and the 96 -h LC0 value was 100 mg/L. In conclusion, the test item was found to cause no toxic effects to zebrafish after 96 hours when tested with a test item solution of 100 mg/L.

Supporting study

An acute fish toxicity study according to the OECD guideline 203 was performed under static conditions. Zebra fish (ten per concentration) were treated with 100.0, 300.0 and 1000.0 mg/L of the test material (60% act. ingredient) for 1, 4, 24, 48, 72 and 96 hours. The LC50 value is greater than 1000 mg/L 48 hours and 96 hours.

Short-term toxicity to aquatic invertebrates

In the acute immobilisation test with Daphnia magna (STRAUS), the effects of the limit concentration of 114 mg/L test item were determined under static conditions over a period of 48 hours according to OECD 202 (2004), equivalent to the Council Regulation (EC) No 440/2008 Method C.2 (2008). A stock solution of 114 mg/L of the test item was freshly prepared with dilution water before the start of the exposure (at 0 hours), homogenised by manual agitation and used for testing. Corrected for purity, the limit concentration was 100 mg/L of pure (anhydrous) substance. The test item solution was red coloured and visually clear throughout the exposure period. Twenty daphnids were exposed to the limit concentration and the control. The concentrations of the test item were analytically verified via spectrophotometric analysis at the start (0 hours) and at the end of the exposure (48 hours) in the limit concentration and the control. The measured concentration in the limit concentration of the test item at the start of the exposure (0 hours) was 107 mg/L and 106 mg/L at the end of the exposure (48 hours). The measured test item concentrations were within ± 20 % of the nominal concentration. This indicates that the limit test item concentration was successfully maintained for the duration of the test. Therefore, the effect levels were based on the nominal concentration of the test item, corrected for purity. The water quality parameters (i.e. pH-value and dissolved oxygen concentration), measured at the start (0 hours) and at the end of the exposure (48 hours), were within the acceptable limits. The validity criteria of the test guidelines were fulfilled. At the limit concentration of 114 mg/L of the test item, which is equivalent to 100 mg/L pure (anhydrous) substance, no effects were observed on Daphnia magna. In conclusion, the following endpoint values were determined on the basis of the nominal test item concentrations, corrected for purity after 24 h and 48 h of exposure: EC10-, EC50- and EC100-value is greater than 100 mg/L.

Toxicity to aquatic plants other than algae

The effects of test item on the growth of the monocotyledon species Lemna gibba was determined according to the principles of OECD 221 under GLP conditions. Each test concentration was freshly prepared with dilution water from a stock solution of 400 mg/L. The tested solutions were visually clear throughout the exposure. A semi-static exposure over 7 days was carried out. Based on a preliminary test, 5 nominal test item concentration levels were tested in a geometrical series with a dilution factor of 2.5: 10.2 - 25.6 -64 - 160 - 400 mg test item/L. Corrected for purity, the test concentrations were 8.98 - 22.5 - 56.3 - 141 - 352 mg/L. Three replicates were investigated for each test concentration and six for the control. Frond numbers were assessed on days 0, 3, 5 and 7. Environmental parameters (light, pH and temperature) were within the acceptable limits. The validity criteria of the test guideline were fulfilled. The concentrations of the test item and the control were analysed via spectrophotometric analysis at the beginning and end of the exposure and at every renewal day. Freshly prepared and old media were analysed. The measured concentrations of the test item in the fresh and old test media were in the range of 89 to 95 % and 92 to 103 % of the nominal values, respectively. All effect values are given below based on nominal test item concentration, corrected for purity.

Based on frond number (after 7 days):

NOEC (growth rate): 56.3 mg/L

LOEC (growth rate): 141 mg/L

ErC50: > 352 mg/L

ErC20: > 352 mg/L

ErC10: 52.4 mg/L (95% confidence limits 25.5 - 103)

NOEC (Yield): 56.3 mg/L

LOEC (Yield): 141 mg/L

EyC50: > 352 mg/L

EyC20: 65.4 mg/L (95% confidence limits < 8.98 – 140)

EyC10: < 8.98 mg/L

Based on dry weight (after 7 days):

NOEC (growth rate): < 8.98 mg/L

LOEC (growth rate): 8.98 mg/L

ErC50: > 352 mg/L

ErC20: 32.8 mg/L (21.8 - 45.8)

ErC10: < 8.98 mg/L

NOEC (Yield): < 8.98 mg/L

LOEC (Yield): 8.98 mg/L

EyC50: 58.1 (95% confidence limits 40.0 - 84.9)

EyC20: < 8.98 mg/L

EyC10: < 8.98 mg/L

 

Toxicity to microorganisms

An activated sludge respiration inhibition test with the test substance was conducted according to OECD guideline 209. The test substance was added in the required amounts according to the test concentrations (62.5, 125, 250, 500 and 1000 mg/L) directly to the test vessels with deionized water. Subsequently synthetic medium were dosed to each test vessel with the test substance. After addition of inoculum suspension (3 g/L dry weight) the incubation was started by aeration of the test vessels with pressured air. The oxygen uptake of each test concentration, the reference substance and the blank control was measured after 3 hours of exposure for a period of about 8 to 10 minutes or until the oxygen concentration fell below 2 mg/L.

An EC10 >1000 mg/L, EC20 >1000 mg/L, EC50 >1000 mg/L, EC80 >1000 mg/L were found in the activated sludge respiration inhibition test with 3 hour residence time for the test substance.